WASHINGTON - H1N1 swine flu killed an estimated 3,900 Americans from April to October, U.S. health officials said on Thursday.

Better estimates show that the pandemic of flu has infected an estimated 22 million Americans and put 98,000 in the hospital, the U.S. Centers for Disease Control and Prevention said. Of these totals, children account for 8 million of the infected, 36,000 of those in hospital and 540 deaths.